CN115036610A - Cooling method and cooling system for battery - Google Patents

Cooling method and cooling system for battery Download PDF

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Publication number
CN115036610A
CN115036610A CN202210209663.9A CN202210209663A CN115036610A CN 115036610 A CN115036610 A CN 115036610A CN 202210209663 A CN202210209663 A CN 202210209663A CN 115036610 A CN115036610 A CN 115036610A
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battery
cooling
cooling device
latent heat
heat accumulator
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Chinese (zh)
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N·齐格勒
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Wokoport Ltd
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Wokoport Ltd
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/60—Heating or cooling; Temperature control
    • H01M10/65—Means for temperature control structurally associated with the cells
    • H01M10/656—Means for temperature control structurally associated with the cells characterised by the type of heat-exchange fluid
    • H01M10/6567—Liquids
    • H01M10/6568—Liquids characterised by flow circuits, e.g. loops, located externally to the cells or cell casings
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/60—Heating or cooling; Temperature control
    • H01M10/61—Types of temperature control
    • H01M10/613—Cooling or keeping cold
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B64—AIRCRAFT; AVIATION; COSMONAUTICS
    • B64D—EQUIPMENT FOR FITTING IN OR TO AIRCRAFT; FLIGHT SUITS; PARACHUTES; ARRANGEMENT OR MOUNTING OF POWER PLANTS OR PROPULSION TRANSMISSIONS IN AIRCRAFT
    • B64D27/00—Arrangement or mounting of power plants in aircraft; Aircraft characterised by the type or position of power plants
    • B64D27/02—Aircraft characterised by the type or position of power plants
    • B64D27/24—Aircraft characterised by the type or position of power plants using steam or spring force
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B64—AIRCRAFT; AVIATION; COSMONAUTICS
    • B64D—EQUIPMENT FOR FITTING IN OR TO AIRCRAFT; FLIGHT SUITS; PARACHUTES; ARRANGEMENT OR MOUNTING OF POWER PLANTS OR PROPULSION TRANSMISSIONS IN AIRCRAFT
    • B64D33/00—Arrangements in aircraft of power plant parts or auxiliaries not otherwise provided for
    • B64D33/08—Arrangements in aircraft of power plant parts or auxiliaries not otherwise provided for of power plant cooling systems
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
    • H01M10/44—Methods for charging or discharging
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/60—Heating or cooling; Temperature control
    • H01M10/62—Heating or cooling; Temperature control specially adapted for specific applications
    • H01M10/625—Vehicles
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/60—Heating or cooling; Temperature control
    • H01M10/64—Heating or cooling; Temperature control characterised by the shape of the cells
    • H01M10/643—Cylindrical cells
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/60—Heating or cooling; Temperature control
    • H01M10/65—Means for temperature control structurally associated with the cells
    • H01M10/655—Solid structures for heat exchange or heat conduction
    • H01M10/6554—Rods or plates
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/60—Heating or cooling; Temperature control
    • H01M10/65—Means for temperature control structurally associated with the cells
    • H01M10/655—Solid structures for heat exchange or heat conduction
    • H01M10/6556—Solid parts with flow channel passages or pipes for heat exchange
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/60—Heating or cooling; Temperature control
    • H01M10/65—Means for temperature control structurally associated with the cells
    • H01M10/658—Means for temperature control structurally associated with the cells by thermal insulation or shielding
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/60—Heating or cooling; Temperature control
    • H01M10/65—Means for temperature control structurally associated with the cells
    • H01M10/659—Means for temperature control structurally associated with the cells by heat storage or buffering, e.g. heat capacity or liquid-solid phase changes or transition
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/20—Mountings; Secondary casings or frames; Racks, modules or packs; Suspension devices; Shock absorbers; Transport or carrying devices; Holders
    • H01M50/204—Racks, modules or packs for multiple batteries or multiple cells
    • H01M50/207—Racks, modules or packs for multiple batteries or multiple cells characterised by their shape
    • H01M50/213—Racks, modules or packs for multiple batteries or multiple cells characterised by their shape adapted for cells having curved cross-section, e.g. round or elliptic
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/20—Mountings; Secondary casings or frames; Racks, modules or packs; Suspension devices; Shock absorbers; Transport or carrying devices; Holders
    • H01M50/249—Mountings; Secondary casings or frames; Racks, modules or packs; Suspension devices; Shock absorbers; Transport or carrying devices; Holders specially adapted for aircraft or vehicles, e.g. cars or trains
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
    • H02J7/0068—Battery or charger load switching, e.g. concurrent charging and load supply
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B64—AIRCRAFT; AVIATION; COSMONAUTICS
    • B64C—AEROPLANES; HELICOPTERS
    • B64C27/00—Rotorcraft; Rotors peculiar thereto
    • B64C27/04—Helicopters
    • B64C27/08—Helicopters with two or more rotors
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M2220/00—Batteries for particular applications
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M2220/00—Batteries for particular applications
    • H01M2220/20—Batteries in motive systems, e.g. vehicle, ship, plane
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T50/00—Aeronautics or air transport
    • Y02T50/60—Efficient propulsion technologies, e.g. for aircraft

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Manufacturing & Machinery (AREA)
  • Aviation & Aerospace Engineering (AREA)
  • Power Engineering (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • Secondary Cells (AREA)
  • Battery Mounting, Suspending (AREA)

Abstract

The invention relates to a cooling method and a cooling system for a battery, in particular for an electric aircraft, having at least one battery cell and a battery cooling device having at least one latent heat accumulator, having the following method steps: A. transferring the first heat from the battery cell to the latent heat accumulator, whereby a phase change occurs in a phase change material of the latent heat accumulator; B. removing the battery from the aircraft; C. establishing an operative connection of the battery cooling means with the cooling circuit of the separate second cooling means; D. flowing a coolant through the cooling circuit; E. transferring the second heat from the latent heat accumulator to the coolant, whereby a phase change occurs in the phase change material of the latent heat accumulator; F. the battery cooling device is separated from the cooling circuit. It is important that method step E and/or method step F are at least partially carried out simultaneously with the charging process of the battery.

Description

Cooling method and cooling system for battery
Technical Field
The invention relates to a method for cooling a battery for an electric aircraft. The invention also relates to a cooling system for at least one battery unit of an electric aircraft.
Background
The electrical or partially electrical (hybrid) driven aircraft is usually powered via a battery. For this purpose, a secondary battery, i.e., a rechargeable battery, which is periodically replaced, is generally used.
An electric aircraft is known, for example, from DE 102012202698 a1, which aircraft comprises at least one battery unit and a plurality of electric drive units. The battery unit serves for storing and outputting the electrical energy required for operating the electric drive unit of the aircraft.
In flight operation, the battery cells are discharged during the discharge process. Likewise, the discharging process may have already begun before the flight operation, for example when the onboard electronics or auxiliary devices of the aircraft require electrical energy.
For a discharged battery, the discharged battery unit must be recharged during the charging process before the aircraft can resume its further operation. In contrast to the discharging process, the charging process is usually carried out in a stationary state of the aircraft. Here, the battery cell is connected to a voltage source, whereby the state of charge of the battery cell is reestablished. The term "battery cell" therefore also extends to rechargeable accumulators. In the following, the terms "battery", "battery unit" and "accumulator" are used interchangeably.
The discharge process and the charge process of the battery cell are performed by chemical reactions in the battery cell. The reaction causes heat generation in the battery cell. In principle, the heat generation depends on the discharge rate and the charge rate of the battery cell, that is, on the amount of electric power released or absorbed by the battery cell.
The heat occurring during the discharge process and the charging process can be dissipated by the battery cooling device.
Battery cooling devices with air cooling are known from the prior art. For this purpose, a plurality of lithium ion circular battery cells are arranged with a large distance therebetween. Here, intermediate spaces are formed between the lithium-ion circular battery cells, in which an air flow can flow and/or circulate. The air flow ensures convective heat dissipation via the surface of the battery cell. The disadvantage here is that the large spacing between the battery cells results in a correspondingly large required installation space. Another disadvantage with air-cooled battery cells is that the more fire-retardant material is provided around the battery cell, the less efficient the cooling. If the fireproof material is omitted, the safety level of the battery is reduced.
Furthermore, battery cooling devices are known which have a cooling plate through which a liquid cooling medium flows. Such a cooling plate can be in thermal contact with the battery cells to be cooled and connected to a cooling circuit. By correspondingly dimensioning the cooling capacity of the cooling circuit, a higher heat quantity can be dissipated in a shorter time. Furthermore, the surface dimensions required for the thermal contact between the battery cell and the battery cooling device can be designed to be small when the cooling power is high. The cooling plate may be disposed to the side, above, or below one or more battery cells. A disadvantage of such battery cooling devices is that many of the cooling media used are flammable and environmentally hazardous, and the cooling devices have a high weight which has to be carried in the aircraft.
The latent heat accumulator constitutes another possibility known from the prior art for removing heat from the battery cells, as described in document US2015037647a 1. Unlike conventional materials, this material has a constant phase transition temperature. This means that, during a change in the state of the latent heat accumulator, heat can be supplied to or removed from the latent heat accumulator within a certain temperature range, while its temperature does not change. By absorbing heat, the Phase Change Material (PCM) of the latent heat accumulator changes phase more, for example from a solid to a liquid/viscous state.
When using a latent heat accumulator for cooling battery cells in aircraft, the temperature of the battery cells or battery cooling does not change significantly thereby, but rather the phase change of the latent heat accumulator, usually from the solid state to the liquid/viscous state, takes place primarily in the form of an isothermal state change. Since, as mentioned above, batteries for electric aircraft are usually designed as rechargeable accumulators, the phase change of the latent heat accumulator must be reversed before the battery or the battery cooling device continues to operate or is operated next in order to be able to reproduce a good cooling action. This reversal of the phase change material of the latent heat accumulator is usually effected by cooling the latent heat accumulator.
In the following, the terms "phase change material" and "latent heat accumulator" are used interchangeably.
Disclosure of Invention
It is therefore an object of the present invention to eliminate the disadvantages of the methods for cooling batteries that exist in the prior art. In particular, cooling of rechargeable batteries should be achieved.
Said object is achieved by a cooling method for a battery according to claim 1. Advantageous embodiments of the cooling method are specified in claims 2 to 4. Furthermore, the object is achieved by a cooling system according to claim 5. Advantageous embodiments of the cooling system are specified in claims 6 to 13. To avoid repetition, these claims are hereby expressly incorporated into this description by reference.
The cooling method according to the invention for a battery of an electric aircraft is carried out with a battery cooling device having a latent heat accumulator, the battery having at least one battery cell. The cooling method comprises the following method steps:
a transfers the first heat from the battery cell to the latent heat accumulator, whereby a phase change occurs in a phase change material of the latent heat accumulator,
b the battery is taken out of the aircraft,
c establishing an operative connection of the battery cooling means with the cooling circuit of the separate second cooling means,
d flowing a coolant through the cooling circuit,
e transferring the second heat from the latent heat accumulator to the coolant, whereby a phase change takes place in the phase change material of the latent heat accumulator,
f separating the battery cooling device from the cooling circuit,
it is important that method step D and/or method step E are at least partially carried out simultaneously with the charging process of the battery.
The object according to the invention is also achieved by a cooling system for at least one battery cell of an electric aircraft. As is known per se, the cooling system comprises a battery cooling device which is designed to absorb at least a first amount of heat from the battery cells during discharge. The battery cooling device is designed with at least one latent heat accumulator with a variable physical state.
It is essential that the cooling system comprises a separate second cooling device which can be thermally coupled to the battery cooling device and is designed to absorb a second heat from the battery cooling device. The cooling system further comprises a charging device for the battery unit, which is designed such that the battery unit can be switched on and charged for a charging process of the battery unit.
The invention is based on the applicant's recognition that a lighter and reliable cooling system is achieved by the combination of a first battery cooling device with a latent heat accumulator arranged on the battery unit and a second cooling device for cooling the outside of the latent heat accumulator. When the two cooling devices are connected to one another by a thermal interface, the cooling of the battery cells by the battery cooling device and the cooling of the latent heat accumulator are thereby carried out offset in time.
The second, separate cooling device is designed to remove heat from the latent heat accumulator of the cell cooling device and thus to reverse the phase change of the latent heat accumulator (also referred to below as reverse reaction or to restore the functionality of the cell cooling device). In addition to the latent heat accumulator, the entire cell, with all components, can also be cooled back to a predetermined starting temperature in order to ensure that the entire cell has the same starting temperature each time the aircraft is started.
At the same time, the battery can be charged during the reverse reaction in the latent heat accumulator for the next use.
The following advantages are thereby obtained in particular: the discharge process of at least one battery unit of the aircraft takes place preferentially during flight operation. Heat is formed at this time. This first heat is conducted approximately isothermally to the phase change material of the latent heat accumulator of the battery cooling device. Here, a phase change takes place in the phase change material of the latent heat accumulator. If the phase change material of the latent heat accumulator is present, for example, as a connecting material, the resulting heat capacity is the average value of the materials present. This results in a slight increase in temperature in this region and no purely isothermal change in state of the latent heat accumulator.
That is, during flight operation, heat can be conducted away using a cooling system having a low weight.
The latent heat accumulator preferably comprises a material such as a paraffin or an ester compound, which can most preferably be incorporated into a polymer matrix. These materials each have a lower density with a high latent heat at the same time. The first quantity of heat is variable in this case and does not necessarily correspond to the temperature increase of the battery occurring as a result of the discharge process, since a part of this heat can also be dissipated as sensible heat on the battery components.
In the stationary state, that is to say generally after flight operation, the battery cooling device is removed from the aircraft and brought into contact with the cooling circuit of the second, separate cooling device via a thermal interface. The thermal interface is a pure thermal interface. That is, the phase change material of the latent heat accumulator of the battery cooling device is in thermal contact with the second cooling device, but no exchange of cooling liquid or the like takes place. The cooling liquid flows only through the second cooling device. The first heat stored in the latent heat accumulator and, if necessary, also other heat generated, for example, by a charging process of the battery, are dissipated via a thermally conductive connection of the latent heat accumulator to the second cooling device.
The reverse reaction of the latent heat accumulator and the charging process of the battery are thereby carried out at least partially simultaneously. For charging, the battery unit is connected to a voltage source, as is known per se. Preferably, after method step B, the battery is pushed into a holder of a ground charging station, which makes it possible to simultaneously charge the battery and cool the latent heat accumulator. The charging of the battery and the restoration of the functionality of the battery cooling device are preferably carried out when the battery is replaced, typically when the aircraft is stopped.
On the one hand, by separating the battery device in the aircraft and on the other hand by the reverse reaction of the latent heat accumulator during the charging process, which is achieved by the second cooling device, advantageously no heavy equipment is required during flight operation, that is to say on board the aircraft, in order to enable the battery cooling device to operate. In particular, heavy and complex components, such as compressors, pumps, valves, heat exchangers, etc., can be arranged outside the aircraft. This results in the advantage that, on the one hand, these components do not have to be certified for transport and/or use on board. On the other hand, these components, which are usually of high weight, do not have to be transported on board the aircraft. Thus, particularly large and high performance components may be used which are impractical or inappropriate for onboard use of the aircraft due to their weight.
In a preferred embodiment of the invention, method step D is carried out after method step C, i.e. the coolant is not continuously present in the second cooling device. In contrast, the coolant is only pumped into the cooling circuit which is in operative connection with the latent heat accumulator for the purpose of carrying out the reverse reaction for reestablishing the functionality of the battery cooling device when an operative connection of the cooling circuit with the latent heat accumulator is established. This achieves the advantage that the cooling tube is expanded and pressed against the housing of the battery by the inflow of coolant in method step D.
The cooling circuit preferably operates on the principle of counterflow heat transfer. This results in the advantage that a temperature distribution of the battery cells which is as uniform as possible is achieved. This is advantageous in particular for a simultaneous charging process of the battery cells.
Optionally, the cooling circuit is configured as a recuperative heat exchanger. This has the advantage that the cooling circuit can be realized with a comparatively simple construction.
In a preferred embodiment of the invention, after method step B, that is to say after the removal of the battery from the aircraft, the battery is pushed into a holder of a ground charging station which makes it possible to simultaneously charge the battery and cool the latent heat accumulator. The second cooling device is preferably part of a stationary ground charging station. The ground charging station has a charging device for the battery unit and is designed to switch on the battery unit to carry out a charging process of the battery unit.
The plurality of batteries of the aircraft are preferably pushed on rails into the retaining device. Between the batteries, a cooling hose is provided, which is connected to an external cooling circuit in the ground charging station. During the pushing-in process, preferably no cooling medium is yet present in the cooling hose. The cooling medium is pumped into the cooling hose only after the battery has been positioned in the holding device, so that the cooling hose expands and presses against the housing of the battery. This results in the advantage that the effective connection between the battery cooling device and the cooling circuit is improved. A further advantage of this embodiment is that tolerances due to production can be compensated for by the flexible cooling hose without the use of so-called "gap fillers" as is otherwise conventional in order to establish good thermal contact, which significantly improves the heat transfer.
Preferably, the second cooling device has at least two cooling hoses and is designed to flow through the two cooling hoses on the counterflow principle. Alternatively, a cooling hose with two connections can also be provided, through which the cooling hose flows on the countercurrent principle.
The phase change material of the latent heat accumulator is preferably designed for a temperature range in which the battery cell heats up in the operating state, preferably in the range from 20 ℃ to 60 ℃, most preferably in the range from 43 ° to 50 ℃.
A further advantage of the invention is that the respective cooling powers of the battery cooling device and the second cooling device can be designed substantially independently of one another. In particular, the first heat quantity has no definite relationship with the second heat quantity. This is primarily because the latent heat accumulator of the battery cooling device can radiate or convectively dissipate a portion of the stored first heat into its surroundings between or during the discharge and charging process. Furthermore, during the charging process, in particular in the case of a rapid charging process, additional heat can be generated in the battery cell, which likewise has to be dissipated preferably by the second cooling device.
The second cooling device is advantageously designed in such a way that the derivable second heat allows a complete reversal of the phase change of the latent heat accumulator of the battery cooling device in order to restore the functionality of the battery charging device and additionally to derive the heat generated during the charging process.
Preferably, the second cooling device has a flexible hose through which a coolant can flow. The contact pressure and the heat transfer achieved by the thermal contact are directly correlated here, the higher the contact pressure, the higher the contact resistance and thus the higher the heat transferred. The flexibility of the hose can thus be used to adjust the pressing force directly by the pressure of the cooling medium. If the flexible hose is filled with coolant under pressure, the hose expands. This increases the contact pressure, so that the amount of heat that can be dissipated increases.
Preferably, the battery has a base plate to which an electrically insulating structure in the form of a film, preferably a kapton (polyimide) film, is glued on the side of the battery cell. The negative electrodes of the battery cells are affixed to the electrically insulating structure of the base plate using a thermally conductive adhesive or thermally conductive resin. The outer side of the bottom plate is in direct contact with a second cooling means in the form of a cooling hose. The binding medium (resin or adhesive), the electrically insulating film and the bottom plate form a thermal interface between the negative electrode of the battery cell and the second cooling means. The cell and the material of the latent heat accumulator which is in contact with the cell are cooled by this thermal interface. The short circuit between the battery cells is avoided by designing the base plate as an electrically insulating layer.
Preferably, the bottom plate is made of a carbon fiber material T700S.
In a preferred embodiment of the invention, the phase change material of the latent heat accumulator of the battery cooling device is encapsulated macroscopically (makreverkappselt) in a carrier matrix. If a material such as paraffin or an ester compound is used as the phase change material, the latent heat accumulator loses a fixed shape by phase change, i.e., the phase change material melts. The shape stability of the latent heat accumulator is ensured by encapsulation in a carrier matrix.
The phase change material of the latent heat accumulator of the battery cooling device is preferably configured as a sleeve around the battery cell. The advantage is obtained by designing and arranging the phase change material in the form of a sleeve around the individual battery cells that a large contact surface between the battery cells and the phase change material can be utilized for heat transfer. Furthermore, a uniform heat distribution is achieved within a single battery cell. Thereby improving the lifespan of the battery cell. Optionally, the phase change material is configured in the form of a plate-like housing surrounding at least part of the plurality of battery cells or in the form of at least one perforated plate. This is advantageous for the manufacture and installation of the battery.
In a preferred embodiment of the invention, the second cooling device is part of a stationary ground charging station. The ground charging station has a charging device for the battery unit, and the ground charging station is designed to electrically connect the battery unit for a charging process of the battery unit. This results in the advantage that the battery can be replaced in a simple manner and manner when the aircraft lands or temporarily lands and with a newly charged battery with a reset battery cooling device. For this purpose, the ground charging station preferably has a holder for the battery, which is designed to connect the second cooling device to the battery cooling device in a thermally conductive manner.
All the negative poles of the battery cells advantageously point in the same direction. The reason for this is that the cell negative electrode has a significantly larger area than the cell positive electrode, which makes it possible to achieve a significantly more efficient heat transfer. Another reason is that, due to the arrangement, hot and toxic exhaust gases can be conducted through the CID valve arranged on the positive side of the battery cell into a system, by means of which said gases can be conducted away from the battery, in the event of thermal runaway of the battery cell.
In this arrangement, the battery cells are preferably wired using a wire bonding method (Drahtbondverfahren) in such a way that the battery has a busbar and the battery cells are preferably connected to the busbar in an electrically conductive manner by means of at least one wire bonding structure. For this purpose, the battery cells are oriented identically, but they are interconnected in parallel and in series. In a common wire bonding method, also known as wire bonding, two terminals are provided on one side of the battery cell, e.g. a housing ring with a negative pole is located directly beside a positive pole cap. In this way, the two poles can be electrically connected on the same side of the battery cell, preferably on the side of the positive pole. The thermal contact is preferably made on the side of the oppositely situated cathode, since the contact surface of the cathode is larger.
The circular battery cell has a high mechanical bending stiffness. Thereby, by the same geometrical orientation of the battery cells, the overall stiffness of the battery may be increased and the risk of damage to the battery may be reduced.
In a preferred embodiment of the invention, the battery comprises a fire-resistant material which at least partially surrounds the battery cell. Preferably, the phase change material of the latent heat accumulator is surrounded by a fire protection material or is integrated in the fire protection material, and the fire protection material is formed with at least two layers. Here, the first layer of fire-resistant material is configured as a mechanically stable structure and the second layer of fire-resistant material comprises a hydrated material.
In the case where thermal runaway occurs in the battery cell, high temperature occurring in the thermal runaway is absorbed by the hydrated material of the second layer of the fireproof material. Such a material undergoes a phase change and can thus absorb at least part of the energy released in the form of heat while keeping the temperature the same.
Furthermore, the first layer, which is formed in a mechanically stable manner by means of the fire-resistant material, prevents the battery cell from bursting. Thereby protecting the adjacent battery cells from both occurrence of critical temperature and mechanical damage due to metal cracking or the like. Therefore, the adjacent battery cells do not enter the critical temperature range by themselves, which also causes thermal runaway of the adjacent battery cells.
The invention is particularly suitable for applications in safety-critical areas, such as manned and unmanned air traffic. Further details of the application possibilities are described in the applicant's application filing 3/5/2020Please refer to Batterieek ü hlvorticichung mit Brandshuttzmaterial, Batter-iemodul mit Brandshuttzmaterial souwie
Figure BDA0003532675770000101
"and" Batterieek ü hlvoricrhtung, Batteriemodul souwie
Figure BDA0003532675770000102
"in (1).
Drawings
Further preferred features and embodiments of the method according to the invention and of the cooling system according to the invention are explained below with reference to the examples and the figures. These examples and the measures which can be provided are merely advantageous embodiments of the invention and are therefore not limiting. Here, the
Fig. 1 shows an exploded view of a battery;
FIG. 2 shows a front cross-sectional view of a battery;
FIG. 3 illustrates a cooling system and a multi-rotor aircraft according to the present invention;
fig. 4 shows a schematic view of a holder for a battery.
Detailed Description
Fig. 1 shows an exploded view of a battery 3, which is shown in a sectional view in fig. 2.
The battery cells 5 of the battery 3 are designed as lithium-ion round battery cells and are arranged geometrically symmetrically.
The battery unit 5 is surrounded on the circumferential surface by a sleeve 19. The sleeve 19 is in the present case made of the phase change material and the fire-resistant material of the latent heat accumulator. This forms a direct thermal contact between the battery cells 5 and the latent heat accumulator 19.
The latent heat accumulator is in the present case made of a composite material in which the phase change material is incorporated in the form of large-scale encapsulation in a carrier matrix. As the phase change material, for example, a material such as paraffin or an ester compound can be used.
The fire-resistant material is configured in two layers in that the first layer of the fire-resistant material is configured in the form of a fiberglass layer as a mechanically stable structure. The second layer of the fire-resistant material consists of a hydrated material, in the present case crystal water.
The mechanically stable layer of fire-resistant material prevents the cell from bursting laterally in the event of an overpressure in the event of thermal runaway in one of the cells. The second layer of the fire-resistant material, which consists of crystal water, serves to evaporate the water contained in this layer to absorb the heat released during thermal runaway. The temperature of such a material may be kept constant during the phase transition of the crystallization water, thereby protecting the adjacent battery cells from overheating.
The first battery cell holder 20 or the second battery cell holder 21 is disposed above or below the battery cell. The first and second battery cell holders 20, 21 serve to spatially fix the battery cell 5 in the housing of the battery 3, so that it is not necessary to support the forces acting on the battery cell 5, which may occur, by means of the sleeve 19.
A housing (not shown) is disposed around the components.
In order to avoid short-circuiting of the battery cells 5, an electrically insulating layer 23 is provided. On the electrically insulating layer 23 a base plate 14 is provided as part of the housing of the battery. This layer is in contact with the cooling hose 9 in the second cooling device, see fig. 4. The material of the battery cells 5 and of the latent heat accumulator 19 which is in contact with the battery cells is in thermal contact with an external second cooling device via the base plate 14 and the electrically insulating layer 23. The base plate 14 and the electrically insulating layer 23 thus constitute a thermal interface between the battery cooling means and the separate second cooling means.
Fig. 3 shows a cooling system with a ground charging station 25 and a multi-rotor aircraft 1. The cooling system extends to a battery cooling device, which is usually located on board the multi-rotor aircraft 1 in the operating state, and to an external, separate, second cooling device 26 in a ground charging station 25.
During flight operation, the battery 3 discharges and releases heat to the latent heat accumulator 19. At a standstill, the battery 3 is removed from the aircraft 1 and pushed into the holder 24 of the ground charging station 25.
The charging process of the battery is used to restore the "used" latent heat accumulator 19 to its original state, that is to say to restore the liquid/viscous phase change material of the latent heat accumulator 19 to its solid state. For this purpose, the battery 3 is removed from the aircraft and switched on electrically and thermally in a ground charging station 25.
For this purpose, the ground charging station 25 comprises a second cooling device 26. The second cooling device 26 has a cooling circuit 27 with a coolant container 28 and a coolant 13 in the coolant container. The pump 29 delivers the coolant 13 through a heat exchanger 30 and via an inflow 31 to a flexible cooling hose (not shown). The cooling hose extends in a bracket 24 into which the battery 3 from the aircraft is inserted (see fig. 4). The warmed coolant 13 flows back into the coolant container 28 through the outflow port 32.
In order to improve the cooling effect of the flexible cooling hose, the cooling hose can be subjected to a high internal pressure. As a result, the cooling tube expands and applies a correspondingly high contact pressure to the component to be cooled, in particular to a thermal interface in the form of the base plate 14 of the battery 3.
The cooling hose is not filled with coolant until the battery 3 is pushed into the holder 24. .
At the same time, the battery cells of the battery 3 are electrically connected to the fixed energy store 11 via the terminals 33 and are charged. The energy store 11 is connected to a generator 34, with which it can be charged after or during a charging process.
According to the invention, the phase change of the heated latent heat accumulator is reversed by the illustrated cooling system using active cooling. At this time, the latent heat accumulator 19 in the liquid/viscous state is brought back into the solid state.
After the charging process has ended and the functionality of the latent heat accumulator has been successfully restored, the battery 3 can be removed from the ground charging station 25 and is ready for use again.
Fig. 4 shows a rack 24 for the battery 3, as is typically provided in a ground charging station 25 (fig. 3). The holder 24 comprises a plurality of holding rails into which a plurality of batteries 3 can be pushed. Between the batteries, a cooling hose 9 is provided through which a coolant can flow. The cooling hoses 9 are in thermal contact with the base plates 14 of the batteries 3 in the retaining rails, respectively.

Claims (13)

1. A cooling method for a battery of an electric aircraft, the battery (3) having at least one battery cell (5) and a battery cooling device having at least one latent heat accumulator (19), the cooling method having the following method steps:
a transfers a first heat from the battery cell (5) to the latent heat accumulator (19), whereby a phase change takes place in a phase change material of the latent heat accumulator (19),
b removing the battery (3) from the aircraft (1),
c establishing an operative connection of the battery cooling device with a cooling circuit (27) of a separate second cooling device (26),
d flowing a coolant (13) through the cooling circuit (27),
e transferring a second heat quantity from the latent heat accumulator (19) to a coolant (13), whereby a phase change takes place in a phase change material of the latent heat accumulator (19),
f separating the battery cooling device from the cooling circuit (27),
it is characterized in that the preparation method is characterized in that,
the method step D and/or the method step E are/is carried out at least partially simultaneously with a charging process of the battery (3).
2. The cooling method according to claim 1, characterised in that method step E of the cooling method is carried out after method step D of the cooling method, in particular in that the effective connection of the battery cooling device to the cooling circuit (27) is improved by flowing in a coolant in method step E of the cooling method.
3. A cooling method according to claim 1 or 2, characterised in that the cooling circuit (27) operates according to the counter-flow principle.
4. Method according to one of claims 1 to 3, characterized in that after method step C of the cooling method, the battery (3) is pushed into a holder of a ground charging station (25) in order to enable the ground charging station (25) to simultaneously charge the battery (3) and cool the latent heat accumulator (19).
5. A cooling system for at least one battery unit of an electric aircraft, the cooling system (6) comprising a battery cooling device designed to, absorbing at least a first heat from the battery cells (5) during discharge, the battery cooling device comprising at least one latent heat accumulator (19) with a variable object state, characterized in that the cooling system (6) has a separate second cooling device (26), the second cooling device (26) can be thermally coupled to the battery cooling device and is designed to absorb a second heat from the battery cooling device, the cooling system (6) further comprises charging means for the battery unit (5), the charging device is designed to be able to switch on the battery unit (5) and to charge the battery unit (5) in order to carry out a charging process of the battery unit (5).
6. Cooling system according to claim 5, characterized in that the phase change material of the latent heat accumulator (19) of the battery cooling device is encapsulated macroscopically in a carrier matrix, in particular in an optimized surface-to-mass ratio.
7. The cooling system according to claim 5 or 6, characterized in that the phase change material of the latent heat accumulator (19) of the battery cooling device is configured as a sleeve around the battery cells or as a housing surrounding at least part of a plurality of battery cells in plate-like form or in the form of at least one orifice plate.
8. The cooling system according to any one of claims 5 to 7, characterised in that the phase change material of the latent heat accumulator (19) is designed for a temperature range in which the battery cell (5) generates heat in the operating state, preferably in the range of 20 ℃ to 60 ℃, most preferably in the range of 43 ° to 50 ℃.
9. The cooling system according to any one of claims 5 to 8, characterised in that a fire-resistant material is provided, preferably in the form of a sleeve (19) surrounding the battery cell, particularly preferably in combination with the phase change material of the latent heat accumulator (19).
10. Cooling system according to one of claims 5 to 9, characterised in that the second cooling device (26) has at least one flexible hose (9) and/or cooling plate which can be filled with coolant (13) and through which coolant (13) flows.
11. The cooling system according to any one of claims 5 to 10, characterised in that the second cooling device (26) is part of a stationary ground charging station (25), and the ground charging station (25) has a charging device for the battery unit (5), and the ground charging station is designed to be able to electrically switch on the battery unit (5) for a charging process of the battery unit (5).
12. The cooling system according to any one of claims 5 to 11, characterised in that the second cooling device (26) is part of a stationary ground charging station (25), the ground charging station (25) having a holder for a battery (3), and the ground charging station being designed to connect the second cooling device (26) with the battery cooling device in a thermally conductive manner.
13. The cooling system according to one of claims 5 to 12, characterized in that the battery (3) has a busbar and the battery cells (5) are electrically conductively connected to the busbar, preferably by at least one wire bonding structure, in particular in that the battery (3) comprises at least two battery cells (5), preferably more than two battery cells (5), the battery cells (5) each being configured as a cylindrical round battery cell having a negative electrode end side (N) and a positive electrode end side (P), which round battery cells are oriented geometrically identically and are preferably wired on the same side of the battery cell by means of the wire bonding structure.
CN202210209663.9A 2021-03-05 2022-03-04 Cooling method and cooling system for battery Pending CN115036610A (en)

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Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8393580B2 (en) 2008-09-12 2013-03-12 The Boeing Company Modular externally accessible batteries for an aircraft
DE102010055600A1 (en) 2010-12-22 2012-06-28 Daimler Ag Device for cooling battery e.g. high-voltage battery, in lithium ion technology, utilized as traction battery in partially and electrically driven vehicle e.g. electric car, has heat storage arranged at edge of composite of single cells
DE102012202698B4 (en) 2012-02-22 2023-06-07 Volocopter Gmbh aircraft
US9496588B2 (en) 2013-07-30 2016-11-15 Johnson Controls Technology Company Battery module with cooling features
CN205376593U (en) 2015-12-14 2016-07-06 深圳市道通智能航空技术有限公司 Unmanned aerial vehicle battery and unmanned aerial vehicle
WO2018081957A1 (en) 2016-11-02 2018-05-11 深圳市大疆创新科技有限公司 Battery containing device and unmanned aerial vehicle
FR3067860B1 (en) 2017-06-15 2021-04-16 Airbus Group Sas SYSTEM FOR CHARGING AT LEAST ONE BATTERY OF ACCUMULATORS OF A VEHICLE AND PROCESS FOR MANAGING THE RECHARGE OF SUCH AT LEAST ONE BATTERY
US10497996B1 (en) 2018-12-12 2019-12-03 Cora Aero Llc Battery with liquid temperature controlling system
EP3942645A4 (en) 2019-03-22 2022-12-07 Khateeb Razack, Siddique Ali Thermal management system and device

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